Statewide ballot measures to legalize same-sex marriage took the lead in Washington, Maryland and Maine on Tuesday, as proponents of marriage equality hoped to break a string of 32 consecutive losses in statewide votes on the contentious social issue.

Referendum 74 in this state was leading 52.6 percent to 47.4 percent, largely on the strength of support from populous King County and other Puget Sound counties. It was being roundly rejected in Eastern Washington and in more socially conservative counties of Southwest Washington.

In a state that rejected marriage equality in 2009, same-sex marriage was ahead by a narrow 52-48 percent margin in Maine. The contest was an even closer 51-49 percent in Maryland, where Catholic Archbishop William Lori required priests to read a pastoral letter denouncing same-sex marriage from the pulpits of his diocese.

But opponents of same-sex marriage faced a stinging defeat in a fourth state. Minnesota voters were rejecting a state constitutional amendment — relentlessly promoted by Catholic bishops, but opposed by Protestant denominations and Catholic laity — that would have defined marriage as between a man and a woman.

The Referendum 74 battle in Washington was nearly two decades in the making. The fight for gay rights began in the mid-1990′s, and progressed to voter approval of civil unions, aka “anything but marriage,” in November of 2009. The Legislature enacted full marriage rights in February, but opponents forced a statewide vote.

“I was thinking of the last 17 years of this battle: The first (anti-gay) Defense of Marriage Act was filed the first week of my first session: What an ugly time,” State Sen. Ed Murray, D-Seattle, chief sponsor of the legislation, said as he awaited returns.

“At some point in those first three years, the Seattle P-I quoted on the front page then-Rep. Mike Shersted. He said something about putting ‘us’ all in a boat. What a long way we have come.”

Proponents of marriage equality raised more than $12 million, but opponents mounted an 11th-hour media campaign aimed at casting doubt on what would happen if couples of the same sex are permitted to marry. The issue divided the state, on east-west lines but also by age. Young people strongly supported Ref. 74; the elderly were most opposed to it.

“We are raised in this country learning about ultimately successful struggles for civil rights: How is marriage equality any different?” asked Nick Hamilton, a Seattle native, recent Trinity College graduate, who voted by mail from Paris where he is teaching English.

State Rep. Reuven Carlyle, D-Seattle, while not predicting the outcome, said Washington was an ideal place to break the 0-for-32 streak. President Obama, who handily carried Washington, came out in favor of same-sex marriage last May. Sen. Maria Cantwell, D-Wash., also an easy victor, spent time in Ref. 74 phone banks during the last week of the campaign.

“On the surface, Washington is known as the home of Microsoft, Amazon and Starbucks but on a deeper level we represent the best of rugged individualism combined with deeply held values of the common good,” said Carlyle. Amazon, Starbucks and Microsoft brass were generous donors to the Ref. 74 campaign, and business leaders argued that marriage equality would draw talent to the state.

Ref. 74 was opposed by the state’s three Catholic dioceses, with bishops recording videos and issuing pastoral letters against it, and a group called Preserve Marriage Washington — financed by the National Organization for Marriage, which helped defeat the 2009 Maine measure and pass Prop. 8 in California.

The rhetoric got hot. “As a law, Ref. 74 therefore conditions our society to forget and ignore basic realities of human existence and, rather than foster human rights, it is actually offensive to basic human rights and equality,” Catholic Bishop Joseph Tyson of Yakima wrote in a pastoral letter.